Financing
Possibly the most difficult part in entire process: borrowing funding
There is a TON to write about this topic but my bank, Glacier Bank has a wonderful writeup on the topic to help you begin
Highlights
In most instances you need 25% cash down to buy land, but could vary bank to bank
If you buy the land before wanting to build you can possibly use the land as collateral for a construction loan
You can wrap the land downpayment + construction downpayment into one BUT a bank will likely want to see formal plans and a bid from a licensed general contractor first. This can be difficult in a competitive market if land is selling fast. Also, the land often informs building type and scale
Convincing a bank to lend you money directly to build as your own general contractor might be possible but likely not easy
Building yourself with cash is naturally the easiest + easiest way to get better deals from subs…but requires you to have a lot of cash